1. Field of Invention
The invention relates to near field communications (NFC), and more specifically to negotiating communication parameters between near field communications (NFC) capable devices.
2. Related Art
Conventional near field communication (NFC) devices are being integrated into mobile devices, such as smartphones to provide an example, to facilitate the use of these mobile devices in conducting daily transactions. For example, instead of carrying numerous credit cards, the credit information provided by these credit cards could be stored onto a conventional NFC device. The conventional NFC device is simply tapped to a credit card terminal to relay the credit information to it to complete a transaction. As another example, a ticketing writing system, such as those used in bus and train terminals, may simply write ticket fare information onto the conventional NFC device instead of providing a ticket to a passenger. The passenger simply taps the conventional NFC device to a reader to ride the bus or the train without the use of a paper ticket.
Generally, NFC requires that conventional NFC devices to be present within a relatively small distance from one another so that their corresponding magnetic fields can exchange information. Typically, a first conventional NFC device transmits or generates a magnetic field modulated with the information, such as the credit information or the ticket fare information, commonly referred to as a modulated data communication. This magnetic field inductively couples onto a second conventional NFC device that is proximate to the first conventional NFC device. The first conventional NFC device continues to generate the magnetic field without the information, commonly referred to as an unmodulated data communication, to allow the second conventional NFC device to harvest power from the magnetic field. The second conventional NFC device recovers, processes the information, and provides a response to the information transferred from the first conventional NFC device using this harvested power.
However, the first conventional NFC device may continue to provide the unmodulated data communication even after the second conventional NFC device has recovered, processed, and provided the response to the information. Consequentially, internal batteries of the first conventional NFC device may be unnecessarily depleted, a temperature of the first conventional NFC device and/or the second conventional NFC device may unnecessarily rise, security of the first conventional NFC device and/or the second conventional NFC device may unnecessarily be compromised, and/or unwanted interference for other communications devices that are proximate to the first conventional NFC device and/or the second conventional NFC device may be created.
Thus, there is a need for a way to dynamically negotiate one or more communication parameters between near field communications (NFC) capable devices that overcomes the shortcomings described above. Further aspects and advantages of the invention will become apparent from the detailed description that follows.
The invention will now be described with reference to the accompanying drawings. In the drawings, like reference numbers generally indicate identical, functionally similar, and/or structurally similar elements. The drawing in which an element first appears is indicated by the leftmost digit(s) in the reference number.